Guest Post by Ira Glickstein
Solar “light” radiation in = Earth “heat” radiation to Space out! That’s old news to those of us who understand all energy is fungible (may be converted to different forms of energy) and energy/mass is conserved (cannot be created nor destroyed).
My Visualizing series [Physical Analogy, Atmospheric Windows, Emission Spectra, and Molecules/Photons] has garnered almost 2000 comments, mostly positive. I’ve learned a lot from WUWT readers who know more than I do. However, some commenters seem to have been taken in by scientific-sounding objections to the basic science behind the Atmospheric “Greenhouse Effect”. Their objections seemed to add more heat than light to the discussion. This posting is designed to get back to basics and perhaps transform our heated arguments into more enlightened understanding :^)
As I’ve mentioned before, during my long career as a system engineer I’ve worked with many talented mathematical analysts who always provided precise results, mostly correct, but some precisely wrong, usually due to mistaken assumptions. I got into the habit of doing a “back of the envelope” calculation of my own as a “sanity check” on their results. If their results matched within reasonable limits, I accepted them. If not, I investigated further. In those days my analysis was really done using a slide rule and scrap paper, but I now use spreadsheets.
The graphic above is based on an excellent spreadsheet from http://serc.carleton.edu/files/introgeo/models/mathematical/examples/XLPlanck.xls. It uses Planck’s Law to calculate the black body radiation spectrum from the Sun, as observed at the top of the Earth’s Atmosphere. It also may be used to calculate the radiation spectrum from the Earth System (Atmosphere and Surface, see below for explanation) at any assumed temperature. (I will refer to this spreadsheet as “Carleton” in this posting.)
I modified the Carleton spreadsheet to compute the mean Solar radiation per square meter absorbed by the Earth System, which turns out to be 240 Watts/m^2. I then used the spreadsheet to determine the effective mean temperature of the Earth System that would emit an equal amount of energy to Space, and that turned out to be 255 Kelvins (-18ºC which is 1ºF).
Since the mean temperature at the surface of the Earth is 288 Kelvins (+15ºC which is 59ºF), that leaves 33 Kelvins (33ºC which is 58ºF) to be accounted for. Guess how we acount for it?
The yellow curve (above left) shows that Solar radiation is in a tall, narrow “shortwave” range, from about 0.1μm (microns, or millionths of a meter) to about 4μm, which we call ultra-violet, visual, and near-infrared. The vertical axis is Intensity of the radiation, measured in Watts/m^2/μm, and the horizontal axis is Wavelength, measured in μm. If you divide the area under the yellow curve into vertical strips, and add up the total area, you get 240 Watts/m^2.
Since we humans sense the visual portion of this radiation as “light”, that is the name we give it, and that has led to the false assumption that it contains no “heat” (or “thermal”) energy.
The violet curve (above right) shows that, assuming a mean temperature of 255 K, Earth System radiation to Space is in a squat, wide “longwave” range, from about 5μm to beyond 40μm, which we call mid- and far-infrared. If you divide the area under the violet curve into vertical strips, and add up the total area, you get the same 240 Watts/m^2 as is under the yellow curve.
DETAILED EXPLANATION
The graph on the left shows the actual observed Solar radiation spectrum (in red) as measured at the top of the Atmosphere. It is superimposed on a black body model (in blue) showing very good correlation. Thus, while the Sun is not exactly a black body, it is OK to assume it is for this type of “sanity check” exercise.
If you calculate the area under the curve you get about 1366 Watts/m^2. That means that a square meter of perfect black body material, held perpendicular to the Sun, would absorb 1366 Watts.
However, the Earth is not a perfect black body, neither is it a flat surface perpendicular to the Sun! So, to plot the yellow curve at the top of this posting, I had to adjust that value accordingly. There are two adjustments:
- The Earth may be approximated as a sphere, with the Sun shining on only half of it at any given time. The adjustment factor for this correction is 0.25.
- The albedo (reflectiveness) of the Earth system, primarily clouds and light-colored areas on the Surface such as ice, causes some of the Solar radiation to be reflected back out to Space without contributing any energy to the Earth System. The adjustment factor for this correction is 0.7.
After applying these adjustments, the net Solar energy absorbed by the Earth System is 240 Watts/m^2.
The graph on the right shows the black body model for an Earth System at a mean temperature of 255 K, a temperature that results in the same 240 Watts/m^2 being emitted out to Space.
Of course, the Earth System is not a perfect black body, as shown by the graph in the upper panel of the illustration below, which plots actual observations from 20 km looking down. (Adapted from Grant Petty, A First Course in Atmospheric Radiation, Figure 8.2, http://www.sundogpublishing.com/AtmosRad/Excerpts/index.html.)
The actual measured radiation is the dark squiggly curve. Note that it jigs and jags up and down between the topmost dashed curve, which is the black body spectrum for a temperature of 270 K and a lower dashed curve which is the black body spectrum for 230 K. This data was taken over the Arctic, most likely during the daytime. The Petty book also has a graph looking down from over the Tropical Pacific which ranges from 300 K down to 210 K. Observations will vary by tens of degrees from day to night, summer to winter, and Tropical to Polar.
However, it is clear that my result, based on matching 240 Watts/m^2, is within a reasonable range of the true mean temperature of the Earth System as viewed from Space.
NOTE ABOUT THE ABOVE ILLUSTRATION
WUWT readers will notice some apparent inconsistencies in the graphs above. The top and bottom panels, from Petty, peak at 15μm to 20μm, while the purple, blue, and black curves in the middle panel, and the Earth System curves from the Carleton spreadsheet I used (see above) peak in the 9μm to 11μm range. Also, the Petty black body curves peak at a “Radiance” around 100 mW/m^2/sr cm^-1 while the black body curves from Carleton peak at an “Intensity” of around 14 W/m^2/μm. Furthermore, if you look closely at the Petty curves, the labels on the black body curves are mirror image! What is going on?
Well, I know some of the reasons, but not all. (I hope commenters who are more fluent in this than I am will confirm my explanations and provide more information about the differences between “Radiance” and “Intensity”.) I have Googled and Wikied the Internet and am still somewhat confused. Here is what I know:
- The horizontal axis in Petty’s plots are what he calls “Wavenumber”, increasing from left to right, which is the number of waves that fit into a cm (centimeter, one hundredth of a meter).
- This is proportional to the frequency of the radiation, and the frequency is the inverse of the wavelength. Thus, his plots are the mirror image of plots based on wavelength increasing from left to right.
- The spreadsheet I used, and my previous experience with visual, and near-, mid-, and far-IR as used in military systems, always uses wavelength increasing from left to right.
- So, when I constructed the above illustration, I reversed Petty’s curves, which explains why the labels on the black body curves are mirror image.
- Fortunately, Petty also included a wavelength legend, which I faithfully reproduced, in non-mirror image, at the top of each plot.
But, that still does not explain why the Petty black body curves peak at a longer wavelength than the Carleton spreadsheet and other graphics on the Internet. I tried to reproduce Petty’s blackbody curves by multiplying the Carleton values by the wavelength (μm) and that did not move the peak to the right enough. So, I multiplied by the wavelength again (μm^2) and, voila, the peaks agreed! (I hope some WUWT reader will explain why the Petty graphs have this perverse effect. advTHANKSance!)
ANSWERING THE OBJECTIONS TO BASIC ATMOSPHERIC “GREENHOUSE EFFECT” SCIENCE
First of all, let me be clear where I am coming from. I’m a Lukewarmer-Skeptic who accepts that H2O, CO2 and other so-called “greenhouse gases” in the Atmosphere do cause the mean temperature of the Earth Surface and Atmosphere to be higher than they would be if everything was the same (Solar radiation, Earth System Albedo, …) but the Atmosphere was pure nitrogen. The main scientific question for me, is how much does the increase in human-caused CO2 and human-caused albedo reduction increase the mean temperature above what it would be with natural cycles and processes? My answer is “not much”, because perhaps 0.1ºC to 0.2ºC of the supposed 0.8ºC increase since 1880 is due to human activities. The rest is due to natural cycles and processes over which we humans have no control. The main public policy question for me, is how much should we (society) do about it? Again, my answer is “not much”, because the effect is small and a limited increase in temperatures and CO2 may turn out to have a net benefit.
So, my motivation for this Visualizing series is not to add to the Alarmist “the sky is falling” panic, but rather to help my fellow Skeptics avoid the natural temptation to fall into an “equal and opposite” falsehood, which some of those on my side, who I call “Disbelievers”, do when they fail to acknowledge the basic facts of the role of H2O and CO2 and other gases in helping to keep temperatures in a livable range.
Objection #1: Visual and near-visual radiation is merely “light” which lacks the “quality” or “oomph” to impart warmth to objects upon which it happens to fall.
Answer #1: A NASA webpage targeted at children is sometimes cited because they say the near-IR beam from a TV remote control is not warm to the touch. Of course, that is not because it is near-visual radiation, but rather because it is very low power. All energy is fungible, and can be changed from one form to another. Thus, the 240 Watts/m^2 of visible and near-visible Solar energy that reaches and is absorbed by the Earth System, has the effect of warming the Earth System exactly as much as an equal number of Watts/m^2 of “thermal” mid- and far-IR radiation.
Objection #2: The Atmosphere, which is cooler than the Earth Surface, cannot warm the Earth Surface.
Answer #2: The Second law of Thermodynamics is often cited as the source of this falsehood. The correct interpretation is that the Second Law refers to net warming, which can only pass from the warmer to the cooler object. The back-radiation from the Atmosphere to the Earth Surface has been measured (see lower panel in the above illustration). All matter above absolute zero emits radiation and, once emitted, that radiation does not know if it is travelling from a warmer to a cooler surface or vice-versa. Once it arrives it will either be reflected or absorbed, according to its wavelength and the characteristics of the material it happens to impact.
Objection #3: The Atmospheric “Greenhouse Effect” is fictional. A glass greenhouse works mainly by preventing or reducing convection and the Atmosphere does not work that way at all.
Answer #3: I always try to put “scare quotes” around the word “greenhouse” unless referring to the glass variety because the term is misleading. Yes, a glass greenhouse works by restricting convection, and the fact that glass passes shortwave radiation and not longwave makes only a minor contribution. Thus, I agree it is unfortunate that the established term for the Atmospheric warming effect is a bit of a misnomer. However, we are stuck with it. But, enough of semantics. Notice that the Earth System mean temperature I had to use to provide 240 Watts/m^2 of radiation to Space to balance the input absorbed from by the Earth System from the Sun was 255 K. However, the actual mean temperature at the Surface is closer to 288 K. How to explain the extra 33 K (33ºC or 58ºF)? The only rational explanation is the back-radiation from the Atmosphere to the Surface.
Mr. Springer gets emotional:
“You’re in denial – either mentally or emotionally unable to accept physics facts derived by both theory, experiment, and widespread employment in practical applications.”
Wellll, I think the Title and significant quote from WUWT today helps put you in your deserved place: http://wattsupwiththat.com/2011/05/16/people-underestimate-the-power-of-models-observational-evidence-is-not-very-useful/#more-39837
When you can offer something besides models (calculations which include only a couple of perhaps dozens of variables), then I will bow to your religion.
BTW, the f-word makes you look silly.
“
@joel
You seem to have lost the plot in the physics of downwelling longwave radiation upon the ocean surface. You can not warm water with LWIR. It is physically impossible. All that happens is the evaporation rate increases. Again following the pesky basic physics involved the water vapor will be at the same temperature as the liquid water which was evaporated. The LWIR energy is in latent heat of vaporization. Once again the physics become inconvenient as water vapor, being lighter than air and thus must necessarily rise carrying all your beloved downwelling LWIR energy back into the sky from whence it came depositing it far from surface when adiatic cooling causes it to condense. Adding insult to injury now at this point (the sadist in me I guess) the ballyhooed insulating effect of greenhouse gases now serves to insulate the surface against the LWIR eminating from the newly condensed vapors and makes the path of least resistance radiative transfer out to the cold dark cosmic void.
Thanks for playing. You were a great sport right up until realized that LWIR cannot insulate a body of water.
If you care to shift your argument to land surfaces we can continue to discuss that because LWIR can certainly insulate rocks. But now that 70% of your potentially insulated surface is gone the GHG effect over land isn’t going to be very consequential. But it’s still good science so I encourage you to continue arguing from your diminished position on dry land.
Addendum to my comment about Mr. Springer goes emotional:
I reread your comment and noticed this factoid of doubtful validity: …”derived by experiment…???
Pray tell where is said experimental evidence?? That is what I crave to get my blinders off!!
The experimental results, so far, show absolutely no OCO-caused warming. Only increases in OCO AFTER warming.
MAYBE, as Misckolski and Wayne seem to think, there is a “ceiling” in the amount of GHE, I can acquiesce. However, the addition of more GHGs to the present system does not appear to be doing squat.
@joel
You say TIGR data is bad because the radiosondes were never designed to measure trends like “that” and satellite data has proven them to be innaccurate.
Well Joel, they’re at least as accurate as the thermometer based surface temperature record.
Fortunately we don’t need accuracy to find trends. All we need for that is repeatability (consistency).
But if you want to play the bad instrument game I allow you to throw out humidity sounding data I’ll have to insist that you throw out the surface station temperature record and only use data available from satellites for that too. I’m a fair guy but won’t tolerate double standards. What’s good for the goose is good for then gander.
Oh sorry, gooses and ganders are biology and we already established biology isn’t your forte. Mibad.
JAE
Nowhere did I say anything about any net warming caused by back radiation from greenhouse gases. All I claimed was that GHGs do indeed absorb radiation and redirect a portion of the absorbed energy back towards the source. This is the basis upon which most electronic CO2 sensors used in commercial ventilation systems work. This so-called back radiation has been physically measured many times by infrared spectrometers looking up from the surface and down from above. It is even verifiable by anyone who beg, borrow, or steal a $50 infrared thermometer
http://www.amazon.com/gp/product/B0017L9Q9C/ref=pd_lpo_k2_dp_sr_2?pf_rd_p=486539851&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B000MX5Y9C&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0A2YZ0RNVN98DZFNB1EG
and verify for themselves that when pointed upward through clear sky it still reads a temperature far closer to the 200-something K of the ground you’re standing on than the 3K temperature of empty space.
If you can’t accept all these things as proof that back radiation is real then you’re a cause and if this was my blog I’d throw your ass out so to reduce the dimwitted clutter that pollutes the more informed converstations.
@ur momisugly Ira
“OK, Wayne, let me agree with you that ALL the individual downwelling photons from H2O, CO2, and all other so-called “greenhouse gases” to the Surface comes from “just 10’s of meters”. As a first approximation I am willing to believe that is actually true for some altitude that is a relatively tiny percentage of the total height of the Atmosphere. So let us draw “Wayne’s line”at that level.”
——
Wayne’s line huh? Sorry, no, you keep changing my words every time, not all GHGs, rare GHG’s as CFCs etc have a mean free path that is long (I’m just guessing due to their very tiny concentration), maybe over a kilometer, maybe even more.
But wait…
You keep seeming intent on making me foolish. I did miss including that the ‘ALL’ is what is measured by a radiometer at the surface upward, but you know, I have said that before above. And yes, photons if you insist to stay on the quantum level mix between layers, but I have said that before. There’s “Wayne’s line”, it’s called a division between chosen layers. And as always, there is never net energy passed downward, but I have said that before. I give. You will never understand what I have said, or will say, and I have said one whole lot of comments above. It is time to stop answering your belittling questions. That’s to me is a shame.
Ira, crx:
There’s no “Wayne’s line”, it’s called a division between chosen layers.
@joel Shore
I just figured out why my comment about oceanic radiative transfers hit a raw nerve with you.
You were a co-author in a critical comment on this paper:
http://www.tech-know.eu/uploads/Falsification_of_the_Atmospheric_CO2_Greenhouse_Effects.pdf
I guess I’m not the first to find the dearth of it passing strange. I had no idea that I was echoing comments made by Gerlich et al. It is quite the extraordinary omission.
Seriously I had no idea when I asked your thoughts about it that it was pressing a button on a sore subject. Of course I’d have asked way sooner if I’d known…
jae says:
May 16, 2011 at 7:22 pm
MAYBE, as Misckolski and Wayne seem to think, there is a “ceiling” in the amount of GHE, I can acquiesce. However, the addition of more GHGs to the present system does not appear to be doing squat.
——
jae, can I clarify? I’m sure that you can’t put Miskolczi’s view with mine, his is a limit on the optical thickness of LWIR through the entire vertical atmosphere.
My concept given above uses the spatial degrees of freedom to calculate the maximum upward flux at a given surface temperature, from the surface upward. I don’t want to tarnish his with mine, if I am off base, could be.
And, my view does not limit the GHE per se, it sets an upper limit on the possible cooling power per a surface temperature and that doesn’t limit the GHE, think of Venus, it insures it’s existence if there are GHG’s present in sufficient enough concentration to have a reasonably short mean free path. But GHE is such a misnomer to me, IMHO it is roughly the local radiative resonance that keeps the air about any point in the atmosphere in radiative and LTE stasis (equipartition across the available degrees of freedom) and therefore maintains maximum warmth and it is performed mainly by GHGs radiation and to a smaller degree, conduction. I though you seemed a bit off my concept.
Tim Folkerts says on May 15, 2011 at 6:39 am:
“2) Suppose a wire is hooked to a battery and we look at a cross-section of that wire. Electrons move:
a) only from + to –
b) only from – to +
c) about evenly in both directions. “
And then he goes on to give the answer i.e. :
“If you answer (a), you are thinking of conventional current, not movement of electrons.
If you answer (b), you have had a bit more training in circuits.
If you answer (c), you are correct.”
Dear Tim the batteries that most people operate with produce Direct Current (DC) and you will find that: “Electricity flows in two ways, either in alternating current (AC) or in direct current (DC). The word electricity comes from the fact that current is nothing more than electrons moving along a conductor, like a wire, that has been harnessed for energy. The difference between AC and DC has to do with the direction in which the electrons flow.
In DC, the electrons flow steadily in a single direction, or “forward.” In AC, electrons keep switching directions, sometimes going “forwards” and then going “backwards.”
Dave Springer says:
Then it ought to be no problem for you to find quotes from reputable scientific organizations representing biologists that say that the consequences of increased CO2 (including climate change) are likely to be more positive than negative and that we should put as much CO2 into the air as we can?
I already explained to you at least some of what is wrong with your picture. For all of your pouncing on jae (which is deserved), your views are really only marginally less nutty than his.
Each data set has its own issues and must be analyzed on its own merits. At any rate, the satellite record is large enough to show most of the temperature rise in the latter half of the 20th century into the 21st.
If I were you, I would not be proud of this fact! Even you will admit that much of their paper is nonsense, in fact, nonsense to such a degree that agreeing with them on something else ought to in-and-of-itself give you pause!
Joel Shore says:
May 16, 2011 at 5:57 pm
Unlikely it was anywhere near that little in your neck of the woods. Global warming or cooling isn’t evenly distributed across the globe spatially or temporally. It’s greater over land than over water. It’s greater in higher latitudes than lower. It’s greater in winter than summer.
But hopefully we’re “committing ourselves” to enough to stop those glaciers from returning. The Holocene interglacial period is long in tooth. You knew that already, right?
Did you also know that the indisputable testimony of the geologic column reveals that even when CO2 was 20 times higher than today that global average temperature was only about 7C warmer than today and this is the normal, most stable climate configuration persisting for a hundred million years or more at stretch and furthermore that this is most biologically productive climate configuration with green plants growing from pole to pole?
I have to ask because you haven’t demonstrated much depth of knowledge in geology or biology in the past or present. This is pretty common knowledge for anyone with a wide grounding in science. Hell I knew all that when I was in grade school. It’s encyclopedic and I had the science sections of the World Book Encyclopedia about memorized by the fifth grade. This is all stuff that was well known in the early 1960’s when I was studying it. Maybe studying isn’t a strong enough word. I was inhaling it.
@Ira
Keep in mind that as LWIR migrates upwards there are fewer and fewer GHG molecules left blocking the view to space and more and more GHG molecules below blocking the view back towards the ground.
The insulating effect of GHGs works in both directions so the higher the emission altitude the easier it is to go upwards and the more difficult it is to go downward. That’s why there’s an extinction altitude for 15um radiation a few kilometers off the ground. At that altitude it become impossible for any emissions to make it back to the surface and they rather all head rapidly out to space from there.
Wayne is quite right. At ground level the prepoderance of emissions hitting your upward looking IR spectrometer originated almost close enough to reach up and touch the source.
@Ira
I’d also remind you that when it comes to GHG molecules first molecules in the emission path do most of the work. Tyndall discovered that 150 years ago. I made an analogy to illustrate likening it to the number of people picking apples in an orchard. For a while every additional picker results in a linear increase in harvest speed but after a while there are so few apples left and/or so many pickers they start competing for the same apples and productivity falls off rapidly. So the first molecules in the upward emission path get the most absorption and re-emission done and as you get higher and higher they start competing for the same
applesphotons and productivity declines exponentially. This also what makes Wayne right about the source of downward emissions – they come from about the height of a tall apple tree or lower.Robert Clemenzi says on May 15, 2011 at 9:59 am:
“O H Dahlsveen says:
May 15, 2011 at 7:00 am
My questions here are: How is it possible for the Atmosphere to radiate 240 W/m² towards space and 320 W/m² towards the surface? – And, what is the “selection method” used by the Atmosphere to enable it to emit more in one direction than it does in the other?
This is rather easy – at some frequencies, the atmosphere is opaque. As a result, the warmer lower atmosphere emits more energy towards the surface than the cold upper atmosphere emits towards space.”
Incorrect Robert, it is not that easy. Radiation is emitted from it’s source equally in all directions. If you do as Joel Shore, Tim Folkerts, Ira Glickstein, Willis Eschenbach and others do and divide the atmosphere up into horizontal layers (all and each one made up, – in our case –not just GHGs but of a mixture of opaque GHGs and other transparent gases) it will mean that once the energy (say 350 W/m²) that relentlessly enters in to the bottom layer from the surface below has had enough energy absorbed for that layer to reach temperature-equilibrium it must emit radiation equally in all directions. And so on – and on, upwards from layer to layer as well as downwards.
If, as according to the plan, 324 W/m² are radiated downwards then 324 W/m² have got to be radiated upwards towards the next layer (hence the origin of the IPCC models’ “Hotspot”.
Do not make the mistaken assumption that the Atmosphere can be likened to a solid piece of, say steel which can easily be warmed more on one side than the other. Such a piece of material will radiate more from the warm side or place than it does from the cooler one.
The Atmosphere progressively gets thinner, or “will contain less atoms and molecules” as altitude increases. That goes for GHGs as much as it does for other gases, which means that radiation will gain more free access to space above in close step with the decrease in opaque gas molecules.
To summarize; “As height is gained each square meter of air will contain less “energy per molecule” but will proportionately let more radiation through from below. – In the end or at the Top of the Atmosphere (TOA), say the Exosphere, each square meter will radiate as LWIR; if the plan is correct, all the incoming/absorbed Solar Irradiation (SI) = 240 W/m² + all the 324 W/m² which the Earth had stored in Oceans, Landmasses and Atmosphere just to keep warm during times when there is no SI which averages near enough 6 months every year. – Due to K& T’s plan we shall soon have a “Snowball Earth””
@Ira
The too many pickers problem is also part of why you can’t slow down the rate of cooling of a body of water with LWIR. The water molecules are so denesly packed in liquid water that the first micrometer absorbs it all. Brownian motion allows the molecules to mix downward another couple micrometers at most but the warmer water is lower density so it wants to fight its way back up to the surface. The end result is there’s virtually no heating beyond the first few micrometers and the molecules near the surface just keep picking up more and more energy as latent heat until they have enough energy to vaporize and then they leave the surface and quickly convect upwards because water vapor is lighter than air. At no point does the average temperature of the vapor exceed the average temperature of the water from which it sprang so the air near the surface never gets any warmer either. The latent heat only becomes sensible again when adiabatic cooling moves it below the dewpoint. This effectively carries off every scrap of downwelling energy up to very near the extinction altitude for 15um and well beyond the extinction altitude of water absorption bands.
We can argue about GHG effect over land which can be substantial but it ain’t a happening thing over water – it’s physically impossible. Liquid water is the uber greenhouse agent to beat all greenhouse agents. Shortwave radiation penetrates easily to a depth of 100 meters while longwave radiation can’t escape except in a billion times thinner layer at the surface and once it escapes it can’t get back in by absorption and reemission by GHGs.
This is why Gerlich et al mockingly said it was amusing that climate boffins calculate the temperature of the earth with and without an atmosphere but don’t calculate it with and without an ocean. The reason is that without an ocean most of the GHG warming disappears. It isn’t the atmosphere doing much of the heavy lifting in that 33C greenhouse warming it’s the ocean doing it.
This giant scientific fraud just keeps getting more and fraudulent the closer you scrutinize it. The biolgical impacts are mostly all bogus, the physics are mostly all bogus, and at this point I’m stuck trying to figure out what small part of the narrative ISN’T bogus. There are grains of truth here and there but they’re not easy to find.
Dave Springer,
Thanks for your extremely good series of posts above. Really excellent. The oceans matter, why is that fact being disregarded?
@Ira
Now that I think about it it shouldn’t be very difficult to remove the ocean from the more sophisticated ocean/atmosphere coupled global circulation models.
I know exactly what will happen. Temperature would plummet all over the globe to below freezing, any GHG warming from water vapor disappears because it all freezes out, albedo shoots up to 90% because where there was once an ocean with almost zero albedo there is snow everywhere with a 90% albedo. It would be COLDER than the moon.
Is anyone here proficient enough with GCMs to diddle with the inputs and subtract the ocean entirely? I predict that when you run the model forward from there the earth will be a frigid snowball everywhere within the first two years.
Smokey says:
May 17, 2011 at 6:40 am
Dave Springer,
“Thanks for your extremely good series of posts above. Really excellent. The oceans matter, why is that fact being disregarded?”
I’m pretty sure the reason is because if you strip the ocean out of the coupled models the earth would be completely covered in snow in a matter of weeks and would stay the way for millions of years while CO2 built up in the atmosphere from volcanic discharges until it was as thick as the Venusion atmosphere and then it would be a runaway greenhouse same as Venus with the final stable state hot enough to melt lead on the surface.
But hey, I’m just guessing and I could be wrong. We can find out by stripping the ocean the best GCMs, hit the execute button, and see what happens.
I doubt the GCMs model CO2 emissions by volcanoes so the current models would just turn the earth into a snowball and stay that way forever.
Dave Springer says: “…the molecules near the surface just keep picking up more and more energy as latent heat until they have enough energy to vaporize and then they leave the surface and quickly convect upwards because water vapor is lighter than air. At no point does the average temperature of the vapor exceed the average temperature of the water from which it sprang so the air near the surface never gets any warmer either. The latent heat only becomes sensible again when adiabatic cooling moves it below the dewpoint. We can argue about GHG effect over land which can be substantial but it ain’t a happening thing over water – it’s physically impossible.”
At sea level, the energy content of the evaporated water molecules will be quite high, but the temperature of the air will not be because most of the air is N2 (temperature is an average), which isn’t heated by IR radiation from the water vapor molecules. If most of the air were changed to CO2, the temperature of this air would increase. That is the GHE.
The GHE does not require that the temperature of the air exceeds the temperature of the ocean surface below it. That would require a huge percentage of the air be water vapor (steam) – we aren’t expecting to boil the oceans.
Water vapor molecules do continue to absorb IR radiation (i.e. “heat up”) after they leave the surface of the ocean. Otherwise the cloud layer wouldn’t be there, we’d just have a global fog layer.
Dave Springer
“This so-called back radiation has been physically measured many times by infrared spectrometers looking up from the surface and down from above. It is even verifiable by anyone who beg, borrow, or steal a $50 infrared thermometer”
What does the comment below mean. From
http://www.slayingtheskydragon.com/en/blog/102-climate-follies-encore
Lord: “Back radiation can be simply demonstrated by pointing a simple infrared detector at the underside of a cloud. Try it.”
Chorus: “My IR detector only cost $60! Simple! Agreed! Agreed!”
Slayer: “Clouds do not absorb and re-radiate heat back to Earth. Clouds add THERMAL MASS which takes longer to heat and cool. Warmists ‘support’ this false hypothesis with IR thermometer readings, but the IR readings of a hot Barbie is the same from any distance; ENERGY is not. Your $60 REMOTE thermometer is not measuring the radiant energy you are receiving, it is measuring the resonance of the Barbie.”
O H Dahlsveen says:
No…Tim is absolutely right. The “drift velocity” responsible for the DC current is many orders of magnitude smaller than the thermal velocities of the electrons. The DC current is produced by only a very slight bias in the electron velocities.
RJ says:
It means that the “Slayers” are talking nonsense, as usual.
Joel Shore says:
May 16, 2011 at 1:49 pm
mkelly says:
I agree. Never said anything different. But it is temperature gradient that matters period. Not back radiation as you and Ira say. I have said several times the two requirements for heat transfer are path and temperature gradient.
“So, what are we arguing about then?” Correct use of terms so everyone can gain knowledge and not “interpret”. Back radiation is not temperaure and no formula you can show someone to demonstrate heat transfer via back radiaion. Not arguing I consider it discussion although insults and slights seem to venture out from some people.
“You admit there is a greenhouse effect?” The atmosphere retards excessive heating and cooling. Moon vs. Earth CO2 does not not heat the ground.
No GHE via CO2. As I have stated before I am more in tune with the hot water bottle world theory.
Dave Springer says:
Unfortunately, your understanding of the greenhouse effect hasn’t progressed beyond what was understood around 1950. The modern understanding is that you have to consider both radiation and convection. You are way too focused on the surface energy budget, which is more difficult to calculate than the budget at the top-of-the-atmosphere. The surface temperature basically ends up being determined by the top-of-the-atmosphere energy budget plus the lapse rate that is basically constrained come through convection, evaporation / condensation, etc. It does not come about by a singular focus on the radiative budget at the surface.